With information communication according to wireless communication, radio waves propagate in space, and information is transmitted to a communication destination. In this case, a part of radio waves directly reach a reception antenna of the communication destination from a transmission antenna. A part of the radio waves reaches the reception antenna of the communication destination after being reflected at a reflective material such as the ground surface, the wall of a building, or the like. Radio waves which directly reach will be referred to as direct waves. Also, radio waves reflected at the reflective material will be referred to as reflected waves. The direct waves and reflected waves are received at the communication destination together. Thus, received power greatly fluctuates depending on reception positions of the radio waves. This fluctuation is called fading. In order to reduce influence of fading, for example, an arrangement has been implemented where radio waves are received by a diversity antenna device which combines multiple antennas (e.g., see Japanese Laid-open Patent Publication Nos. 2003-332834 and 2006-352293).